Pre-RTL formal verification: An Intel experience

During the development of a next-generation Intel processor, the project's formal verification team verified a new coherence protocol and portions of its RTL implementation against the protocol's specification within project deadlines. Typically, FV teams apply formal property verification (FPV) after RTL is coded and, though it continues to be an effective complement to pre-silicon validation, this late application prevents it from keeping pace with the continual complexity increases in hardware designs. Our discussion centers around how applying FV early in the development cycle of this processor enabled continual verification as the design progressed, culminating with the targeted RTL verification. We also present the languages and methodologies used, the reasons behind the choices, and where improvements can be made.